Means for perforating paper and the like



G. s, HELLBERG ETAL 2, 95,959

FUR PERFURAHNG PAPER AND LIKE 3 Sheets-Sheet 1 Filed @431. 8, 1957 Aug.22,, 1961 G. s. HELLBERG ETAL 2,996,959

s ma PWFQRA'HNG 11 mm mm "mm mum 5 Sheets-Sheet 2 Filed @Gt. 8, 1957Fig.

19% s. s. HELLBERG ETAL 2,996,959

ma PERFORMING PAPER m Filed @cat. 8 1957 5 Sheets-Sheet 5 Fig. 5

rates The present invention refers to such methods for the perforationof paper and the like, such as book-keeping leaves and hole cards,wherein the paper is advanced in contact with a rotating pattern roll,having relief-like portions in the form of studs of a shapecorresponding to the shape of the perforated apertures, the perforationsbeing produced by means of one or more rotating tools acting upon thepaper at those portions thereof which fbear against the end surfaces ofsaid studs. It is known to produce perforations by means of cutting andgrinding tools operating to work off the perforated portions of thepaper, while the paper is advanced continuously to gether with thepattern roll past the tools. The present invention relates to a newmethod of producing perforations by means of rotating tools. Theinvention is principally characterized by the fact that the paper ispressed against the pattern roll, so that rupture indications are formedin the paper along the edges of the studs, whereupon the compressedportions of the paper are severed by being torn ofi along said ruptureindications. According to a practical embodiment of the invention thepaper is compressed between the studs of the pattern roll and a pressingtool in the form of a roll, rotating in a direction such that adjacentportions of the pattern roll and the pressing roll move in the samedirection. The peripheral speed of the pressing roll is then greater andpreferably many times greater than that of the pattern roll, so that thepaper, while being compressed, is subjected at the same time to africtional force acting in a tangential direction. Said frictional forcemay be of such magnitude that the compressed portions are torn offimmediately along the rupture indications, thereby causing thecompressed portions to be removed successively in minute parts accordingas the processing of the paper proceeds.

The invention is illustrated in the accompanying drawings which by wayof diagrammatic representation show a form of embodiment of aperforating machine, constructed according to the invention.

FIG. 1 is a view in elevation of the mutual arrangement of the essentialparts of the perforating machine. FIGS. 2 and 3 are sectional views on alarger scale of the two tools by means of which the paper is operatedupon, these views also showing the studs in operative positionsrelatively to said tools. FIG. 4 shows a modification of a stud. FIG. 5is a view in elevation of the pressing tool shown in FIGS. 1-3. FIG. 6shows another embodiment of the pressing tool.

As shown in FIG. 1, a paper web 2 wound onto a supply roll 1 is adaptedto be advanced over a freely running roll 3 and further round thecircumference of the cylindrical surface 5 of the pattern roll 4. Theroll is provided with radially projecting studs and/or pins 6,preferably of steel, which are arranged in positions corresponding tothe desired positions of the perforation apertures on the paper web andwhich have end surfaces corresponding to the shape of the perforationapertures. 'Ihe studs are of a height above the cylindrical surface 5 ofthe roll, which is only slightly greater than the thickness of thepaper. The relative thickness of the paper is shown on an exaggeratedscale in the drawings.

atcnt The studs 6 have a cylindrical envelope surface and across-sectional shape corresponding to the form of the perforationapertures. The pattern roll is driven continuously in the directionindicated by the arrow 7 and entrains the paper web through the frictionbetween the studs and the paper.

During the rotation of the roll 4 the paper web first meets with apressing tool 8 in the form of a roll parallelling the pattern roll andprovided with pressing members rigidly arranged on the cylindricalsurface thereof or milled out from the roll, said pressing memberstaking the form of projecting ribs 9, cams or the like of steel having arounded, preferably semi-cylindrical end surface and adapted to operateupon the paper at those portions thereof which bear against the studs 6.As will be seen from FIG. 5, the ribs extend parallel in an obliquedirection along the pressing roll and alternately in differentdirections, whereby the laterally directed forces acting upon the paperare equalized. The pressing roll it rotates in a direction opposed tothat of the pattern roll, as shown by the arrow 10, the peripheralportions of the pressing roll and the pattern roll then running in thesame direction. The pressing roll, however, has a peripheral speed manytimes greater than that of the pattern roll.

As will appear from FIG. 2 the end surfaces 11 of the studs 6 coincidewith a projected cylindrical surface coaxial to the axis of the patternroll. The end surface 11 is provided with a bowl-shaped cavity 12, sothat an annular edge portion 13 is formed, which has an outer sharp edgeand an inner obtuse or rounded edge. The cavity 12 has for its object toreduce that portion of the paper bearing against the stud, which has tobe processed for the production of a perforation aperture.

When a stud 6 reaches the working range of the pressing roll 8, theportion of the paper supported by the stud will be subjected to anintermittent working by the round edges of the ribs 9, transverselyextending strips of the paper being then compressed successively. Theportion of the paper meeting with the cam will thus be compressed to asuccessively decreasing thickness, which has its lowest value in theposition of the rib coinciding with the plane through the axes of thepattern roll and the pressing roll, in which position the thickness ofthe paper is a fraction of the initial thickness. Through thecompression the paper is weakened, and a rupture indication is formedalong the outer sharp edge of the stud. At the same time the paper isacted upon by a tangentially directed frictional force created by thepressure of the ribs. Under certain conditions depending on thethickness and the strength of the paper and on the nature of the surfacethereof, the compressed portions of the paper might be torn oif from thestud through said frictional force, the severing then taking placepartly in a direction transversally of the stud and partly along theweakened edge line. In the following it will be assumed, at first, thatthe perforated apertures are formed in this manner directly by theaction of the pressing roll. However, the portion of the paper lyingclose to the meeting edge of the stud will not always be uniformly cutin this manner along the edge line of the stud, as it may happen that atorn-up lug i4 is let at this point of the edge of the aperture. Toremove this lug and, besides, to bring about a trimming of the apertureedges, a rotating tool 15 is provided in a position which is angularlydisplaced relatively to the pressing roll in a forward direction. Thistool consists, like the pressing roll, of a cylindrical part providedwith ribs 16 arranged in a similar manner as the ribs 9. The outer edgesof these ribs 16 move in a cylindrical surface, which nearly touches thecylindrical surface 11 of the studs. The tool 15 rotates in thedirection indicated by the arrow, the ribs 16 thus moving in a directionopposed to that of the paper 2. As is the case with the ribs 9, the ribs16 may have a rounded cylindrical edge, but they may also be formed intoa cutting edge. When the portion of the paper already perforated reachesthe tool 15, the remaining lug will be cut off, so that the edge of theaperture becomes entirely uniform at this point too. To ensure that thepaper is in such a position relatively to the fore edge of the stud thatthe lug can be cut off by the ribs 16, a supporting head 18 is providedin front of every stud, having an outer sloping surface supporting thepaper in a position such that the edge of the aperture cannot be pressedfurther down than by an amount corresponding approximately to theinitial thickness of the paper. After the paper has moved past the othertool 15, it is brought round the circumference of a guide roll 19, andfurther to a rewinding drum, not shown. The roll 19 may preferably havea lining 20 of resilient material on the cylindrical surface, and may beso arranged that the paper is pressed by said lining against thecylindrical surface of the pattern roll 4, whereby the aperture edgesabout the studs are smoothed out.

The tangentially directed frictional force exerted by the pressing roll8 has a tendency to displace the paper relatively to the studs of thepattern roll in the forward direction. To prevent such displacement thepaper web may be checked in its movement, for instance by braking theguide roll 3 or the supply roll 1. It is also suitable to oppose thebreaking power by exerting a tractive force on the paper in thedirection of advancement, for instance by means of the guide roll 19,for the purpose of preventing the paper from sliding relatively to thepattern roll during the motion intervals when the pressing roll isinoperative.

In case the tangentially directed frictional force exerted on the paperby the ribs of the pressing roll is not sufficient to tear otf thecompressed portions of the paper, the perforated apertures will beformed when the paper moves past the rotating tool 15, which is soarranged and devised that it may act upon the paper in a tangentialdirection with so great a force that the portion of the paper weakenedthrough the foregoing compression and left on the surface of the stud,will be torn off the stud through the influence of the ribs 16, saidportions being then torn off along the weakening line running round theedge of the stud. In place of a tool with ribs or knives, a roll ofrubber with a smooth cylindrical surface may be made use of, whichbrings about the frictional engagement necessary for the separation ofthe aperture portion of the paper.

In the arrangement described, the ribs 9 of the pressing roll wiiloperate upon the paper intermittently and will thus bring about acertain impact effect, which facilitates the tearing off of thecompressed paper strips. Obviously, such an etfect may also be broughtabout by the surface of the pressing roll being corrugated or slitted,the projecting portions having rounded edges. It is also possible,however, to provide the pressing roll with a smooth cylindrical workingsurface of a diameter such that the surface nearly touches the outercylindrical surface 11 of the studs 6. Under certain conditions, apressing roll of this type with a smooth surface may also exert asuflicient frictional force on the paper to enable the formation of theperforation apertures by tearing off the compressed portions of thepaper. In such case. however, it might be suitable to cause the pressingroll only to bring about a compression of the paper, so that embossmentsare made by depressing the studs into the paper, the removing of thecompressed aperture portions of the paper being then effected by meansof the tool 15 in a manner similar to that hereinbefore described. Insuch case, the pressing roll 8 obviously need not have a peripheralspeed exceeding that of the pattern roll, but may have the sameperipheral speed, so that both rolls perform a rolling motion on oneanother.

In the latter case it will be found suitable to form the stud 6 in themanner shown in FIG. 4. As distinguished from FIGS. 1-3, where theannular surface portion 13 coincides altogether with the cylindricalsurface 11, the corresponding edge portion of the stud is here bevelledoff inwardly, so that the edge 21 lying on the cylindrical surface 11.forms a cutting edge with an acute angle. In the example shown, theannular surface 13 forms the end surface of a hollow cylinder. It isessential that said cutting edge does not cut through the paper but onlybrings about a rupture indication. Consequently, the pressing roll mustnot touch the edge, but there must be a clearance 22 between thecylindrical surface 23 of the pressing roll and the edge or thecylindrical surface 11, said clearance corresponding to the desiredcompression of the paper. The separation of the compressed apertureportion is then effected by means of the other tool 15.

The pressing tool shown in FIG. 6 has the shape of a plane circular disk24, which is rotatable about an axis 25 extending at right angles to theaxis of the pattern roll, and which on the side thereof facing thepattern roll is provided with radially arranged ribs 26 of the same kindas the ribs 9 of the pressing roll 8. As will be seen from FIG. 6, sucha tool will operate in the same manner as the pressing tool 8, so thatthe paper is successively compressed against the end surfaces of thestuds, the strips of the compressed portions being torn off along theedge line weakened through the compression. If desired, the tool may begiven a conical shape, the ribs being then arranged on a conical surfacein the same manner as the teeth of a bevel gear wheel.

Thus, the pressing tool is essentially characterized by the fact thatits actuating parts lie in a surface of rotation touching the paper web,whereas a clearance is provided between said surface of rotation and thepath of movement of the end surfaces of the studs, said clearancecorresponding to the wanted degree of compression of the paper, so thatthe studs will not cut through the paper but only cause a weakening ofthe paper along the outer edges of the studs.

The invention is not limited to the perforation of paper but mayobviously be applied also for the perforation of other materials such asplastic and metal foils in the form of sheets or bands.

What is claimed is:

1. A device for the perforation of paper and the like in web formcomprising, in combination, a rotatable patrix roll provided withrelief-like portions having end surfaces which correspond to the shapeof the perforations to be made, means for feeding the paper in contactwith the end surfaces of said patrix roll, and at least one rotatabletool positioned adjacent said patrix roll to engage said paper to workoff the portions of the paper engaged and Supported by said endsurfaces, said tool being provided with working surfaces free from sharpedges and said tool being rotatable about an axis which is at rightangles to the axis of said patrix roll, the working surfaces of saidtool working in contact with the end surfaces of the relief-likeportions whereby compression between the surfaces is obtained.

2. A device for the perforation of paper and the like in web formcomprising, in combination, a patrix roll rotatable in a first directionand provided with relief-like portions having end surfaces whichcorrespond to the shape of the perforations to be made, means forfeeding the paper in contact with the end surfaces of said patrix roll,and a pair of rotatable ttools positioned adjacent said patrix roll incircumferentially spaced-apart relationsh p to engage said paper to Workoff the portions of the paper engaged and supported by said endsurfaces, said tools being provided with working surfaces free fromsharp edges, the tool which lies upstream with respect to the paper feedbeing rotatable in a second direction which is opposite to said firstdirection and the other tool being rotatable in said first direction,said upstream tool being rotatable about an axis which is at rightangles to the axis of said patrix roll, the working surfaces of saidupstream tool working in contact with the end surfaces of therelief-like portions whereby compression between the surfaces isobtained.

3. A device for the perforation of paper and the like in web formcomprising, in combination, a patrix roll rotatable in a first directionand provided with relief-like portions having end surfaces whichcorrespond to the shape of the perforations to be made, means forfeeding the paper in contact with the end surfaces of said patrix roll,and a pair of rotatable tools positioned adjacent said patrix roll incircumferentially spaced-apart relationship to engage said paper to work01f the portions of the paper engaged and supported by said endsurfaces, said tools being provided with working surfaces free fromsharp edges, the tool which lies upstream with respect to the paper feedbeing rotatable in a second direction which is opposite to said firstdirection and the other tool being rotatable in said first direction,said upstream tool being References Cited in the file of this patentUNITED STATES PATENTS 247,368 Lang Sept. 20, 1881 797,886 Deely Aug. 22,1905 1,121,817 Ferres Dec. 22, 1914 1,573,813 Damm Feb. 23, 19262,429,945 Rayburn Oct. 28, 1947 2,908,201 Hellberg Oct. 13, 1959

